"The crew had flown over and hadn't noticed the sign, but they were so low their rotors blew my shorts up into the air and that was what they saw. That was the reason why they turned around."

The crew told him the helicopter had only 15 minutes of fuel remaining.

Woodhead was taken to a hospital in Longreach, suffering from kidney damage and having lost about 12kg.

Doctors told him his hydration levels were so low he would not have survived for more than a few hours, the Mail on Sunday reported.

Woodhead told the paper he hoped to attend Sandhurst next year to become an army officer. He had set out for a walk from the ranch in Vergemont where he had been working, carrying a heavy backpack as training.

However he lost his bearings and could not make his way back to the ranch, although throughout the ordeal he was never more than about 8-9km away.

With only a litre of water, he told the paper how he survived on sachets of contact lens saline solution, and even tried drinking his own urine.

"I tried to drink it and took a glug. It was like the contact lens solution but ten times worse. I had to drink about three of the contact lens sachets afterwards just to get rid of the taste."

Although Woodhead was concerned the salt content in the saline solution could have done more harm than good, he believes drinking the fluid was what kept him alive.

Detective Sergeant Dave Perry told the paper he was astonished Woodhead survived three days with no water.